TALLAHASSEE — What started as a legislative effort to protect the Hospital Corporation of America from lawsuits over its trauma centers could also clamp down on the for-profit company's outsized trauma response fees, and slow down its plans to open still more facilities.

A yearlong investigation by the Tampa Bay Times found that trauma centers across the state are exploiting a little-known fee that is meant to offset some expenses of high-priced care. But HCA's average $28,000 trauma response fee is by far the highest in the state. The for-profit company now has five Florida trauma centers. If it can win state approval, the company has ambitions to open more.

Sen. Denise Grimsley, R-Sebring, said she read the Times report and concluded the fees were "outrageous." She has proposed an amendment to Senate Bill 1276, intended to protect HCA from legal challenges against three of its trauma centers. Grimsley's proposal would cap the trauma response fee for one year at $15,000, a level that would affect only HCA and one other for-profit trauma center.

Her amendment, which the Senate Health Policy Committee will consider today, also creates a one-year moratorium on opening new trauma centers and convenes an advisory committee to help revise the application and approval process.

The bill, if approved, still would allow the three HCA centers in dispute to stay in operation. Regional Medical Center Bayonet Point in Pasco County, Blake Medical Center in Manatee County and Ocala Regional Medical Center in Marion County all have been challenged by long-standing trauma centers that contend the state should never have allowed them to open.

Bayfront Health St. Petersburg has been particularly hard hit by the opening of the Pasco and Manatee trauma centers.

Grimsley said her amendment "gets the state off the hook and then moves us forward so we have a good, adequate set of trauma centers for Florida."

HCA did not respond to a request for comment from the Times on Monday night.

A separate proposal in the House also protects the three HCA trauma centers but does not touch on trauma center fees or future expansion. HB 7113 was approved by the Health Care Appropriations Subcommittee on Monday with two dissenting votes: Rep. Elaine Schwartz, D-Hollywood, and Rep. Janet Cruz, D-Tampa.

Schwartz said she voted against the bill because the pending court challenges should be argued through the legal system.

"The Legislature is being used to cut off the judicial process," she said.

HCA is a formidable presence in Tallahassee with 25 registered lobbyists to influence legislators this session. It has made $1.3 million in campaign contributions, including $100,000 to the governor's re-election campaign, since November 2012.

Rep. Amanda Murphy, D-New Port Richey, withdrew a proposed amendment to HB 7113 that would have required a study of trauma response fees. She said she agreed to wait until the next committee hearing to raise the issue and decided to support the bill in the interim.

Connie Potter, a trauma industry leader who helped create the trauma fee more than a decade ago, says a $15,000 fee would be in the "upper range" of fees she has seen across the country. What's more, she said, a fee that high could only be justified for the most severely injured patients.

The Times found that thousands of trauma patients with minor injuries have been charged trauma response fees, even though they were sent home just hours after they arrived at a hospital. Some were charged more for the response fee than they were for their actual medical care.

"If everybody that comes in still gets hit with a $15,000 fee and gets discharged two hours later, they're not going to be very happy," she said.

Potter says Grimsley's proposed cap "shows progress," but that the state should consider additional solutions. Trauma centers should be required to justify what they charge based on actual costs, she said. As it stands, hospitals face virtually no government oversight of how they set their charges and patients have no way of knowing what a hospital charges.

While the Florida Agency for Health Care Administration collects trauma fee data, Potter said it also should analyze and publicize the data. And a tiered trauma response system should be created so that patients with less severe injuries do not get the same fees as those who need the life-saving efforts of a full trauma team, she said.

Times staff writer Letitia Stein contributed to this report. Tia Mitchell can be reached at (850) 224-7263 or tmitchell@tampabay.com. Alexandra Zayas can be reached at (727) 893-8413 or azayas@tampabay.com.